code: def assert_orthogonal(u1, u2, rtol, atol):
      """Check that the first k rows of u1 and u2 are orthogonal"""
      A = abs(np.dot(u1.conj().T, u2))
      assert_allclose(
          A, np.eye(u1.shape[1], u2.shape[1]), rtol=rtol, atol=atol
      )
  
file_path: scipy/scipy/sparse/linalg/tests/test_propack.py
imports: import os
  import pytest
  import sys
  import numpy
  from numpy.testing import assert_allclose
  from pytest import raises
  from scipy.sparse.linalg._svdp import _svdp
  from scipy.sparse import csr_matrix, csc_matrix
label_desc: Use image node_id 5 for calling a global function with example usage: assert_orthogonal(u1, u2, rtol, atol) without return types